Tool retainer



E. W. STEVENS TOOL RETAINER Dec. 6, 1927. 1,651,417

Filed Dec. 7. 1924 IN VENTOR Edward W. Sfevens BY A ATTORNEY PatentedDec. 6, 1927.

. UNITED STATES PATENT OFFICE."

EDWARD W. STEVENS, 015 DETROIT, MICHIGAN, ASSIGNOR TO CHICAGO PNEUMATICTOOL COMPANY, OENEW YORK, N. Y., A CORPORATION 01 NEW JERSEY.

TOOL RETAINER.

I Application filed December 17, 1924. Serial No. 756,388.

This invention relates to retaining devices for the working tool ofpercussive machlnes, such for example as pneumatic hammers. Moreparticularly it [relates to devices of th1s character adapted for quickappllcation to and removal from such machines in order to facilitate theinterchange of working tools. This invention is in the nature of animprovement on or further development of a prior invention disclosed inmy copendlng application Serial No. 652,369 filed July 18,

1923, for quick acting tool retainer.

The so-called quick acting retainers such as disclosed in my copendingapplication above noted are quickly released from the percussive machineby a rotative movement of the retainer. As the operator of such amachine ordinarily grasps the retainer with one hand while the other isused on the throttle or switch handle of the machine, it has been foundin practice that the operator at times unconsciously twists the retainerrelative to the machine, thus releasing both the retainer andthe workingtool," which may be projected from the machine by the next impact of thepercussive element and injure some one or damage the work.

One object of the invention is to prevent inadvertent release of theretainer in the manner described. 'Another object is se-' curely'to lockthe retainer in operative position against accidental release but toarrange for quickly unlocking it when its release is intentional anddesired.

In order to illustrate the invention one concrete embodiment thereof isshown in the accompanying drawings, in which:

Figure 1 is a side elevational view of a pneumatic hammer equipped withthe invention.

Figure 2 is an enlarged transverse sectional view substantially on line22 of Figure 1.

Figure 3 is a longitudinal vertical sectional view on an enlarged scaleof the front end ofthe hammer shown in Figure 1 taken on line 33 ofFigure 2.

Fi 4 is a fragmentary longitudinal sectiona l View on the line 44 ofFig. 2.

The embodiment of the invention chosen for the purpose of illustrationconsists of a retainer 4 in the form of a sleeve adapted to betelescopedoverthe cylinder at of a percussive machine such as thepneumatic hammer A shown in Figure 1. This retainer is for the purposeof maintaining inoperative position the Working tool 'B which is actedupon by, the piston of the pneumatic hammer A or other percussivemachine. This working tool may be of any type required by the work to beperformed such as a button set, chisel, drill steel, punch, etc. Inthe'present instance the working tool shown is a chisel 13 held withinthe retainer 4 by the outer inturned flange .or lip 5 of the latter, the

chisel being guided in the end of the cylinder a by a bushing b which isheld in spaced relation to the flange 5 by rubber buffer 6.

The retainer 4 is held on the cylinder a against axial withdrawal byopposed latching blocks 6 normally forced through openings 7 in thesleeve by an arcuate spring 8 seated in a groove defined by spacedcircumferential flanges 9 on the sleeve, the blocks being secured to thespring in any suitable manner as by rivets 10. The latching blocks 6 arearranged to seat in transversecuts or grooves a in the hammer cylinder,said grooves providing stop shoulders a engaged by blocks 6. As will beclear from .Fi 2 rotation of the sleeve retainer 4 in eit er directionrelative to cylinder a will force the latching blocks 6 out of grooves aand permit the retainer to be withdrawn from the cylinder wheneverdesired. The structure so far described conforms substantially to thatof my copending applicationabove referred to.

In order to prevent accidental rotation of the retainer sleeve and itsconsequent release suitable means, comprising the present in-, ventlon,are provided for locking the sleeve in such position that the latchingblocks 6 register with and remain in the cylinder grooves a. Thislocking means preferably takes the form of member 11 (Fig. 2) on thesleeve normally engaging a recess a in cylinder a. Member 11 ispreferably spring pressed to cause it to remain in operative position inrecess a. For simplicity and ease of manufacture and assembly it may bein the form of the bent end of a spring ring 12 seated in acircumferential groove 13 in sleeve 4:, the end 11 being arranged toextend through an opening 14: in the sleeve. In practice it ispreferable to provide the cylinder a with two recesses a properlydisposed relative to. the grooves a so that the retainer sleeve 4 may beconveniently applied to the cylinder a in any position in which theblocks 6 will register with the grooves a. Further and by preference therecesses a are formed as axial grooves and the latching blocks 6 areformed with rearward bevelled surfaces, so that the retainer 4 with theworking tool B therein is readily applied to the hammer cylinder byaligning the locking member 11 with one of the axial grooves a and thendriving the retainer into telescoping relation with the cylinder a by aforceful push or blow. To permit the removal of the retainer forchanging the working tool or for any other reason an axial groove 15(Figures 1 and 2) intersecting circumferential groove 13 adjacentopening 14 is provided on the retainer sleeve 4 for the insertionbeneath locking ring 12 of a pointed instrument such as a nail indicatedat X (Fig. 2) to be used as a lever to pry up the inturned end 11 orlooking memer and remove it from engagement with the locking groove a asindicated in the broken line position of the parts in Fig. 2. Theretainer sleeve 4 can then be rotated to cam the latching blocks 6 outof their grooves a whereupon the retainer is readily removed from thehammer cylinder.

While but one form of the invention has been herein disclosed it is tobe understood that the present invention is not restricted to thespecific details thereof-but covers all modifications and adaptationswithin the spirit of the invention and within the scope of the appendedclaims.

I claim as my invention:

1. The combination with a percussive machine and a working tool thereforof retaining means for said tool comprising a sleeve having latchingmeans for retaining it in operative position on the machine, saidlatching means being releasable by rotation of said sleeve, and means onsaid sleeve operating automatically on application of said sleeve forpositively locking said sleeve against rotation.

2. The combination with a percussive machine and a working tool thereforof retaining. means for said tool comprising a sleeve having latchingmeans for retaining it in operative position on the machine, saidlatching means being releasable by rotation of said sleeve, and aretractable member eooperating with a recess in said machine andoperating automatically on application of said-sleeve to said machinefor positively" locking said sleeve against accidental rotation.

3. The combination with a percussive machine and a working tool thereforof retaining means for said tool comprising a sleeve having latchingmeans for retaining it in operative position on the machine, saidlatching means being releasable by rotation of said sleeve, and aspring-pressed member normally engaging an axial groove in said machinebeneath said sleeve to permit easy application of said sleeve and forpreventing accidental rotation of said sleeve.

4. The combination with a percussive machine and a working tooltherefonof retaining means for said tool comprising a sleeve havinglatching means for retaining it in operative position on the machine,said latching means bein releasable by rotation of said sleeve, a locring member arranged to permit easy application of said sleeve and toengage an axial recess in said machlne to prevent accidental rotation ofsaid sleeve when applied, and a spring ring encircling said sleeve formaintaining said member in locking position.

5. The combination with a percussive machine and a working tool thereforof retaining means for said tool comprising a sleeve having latchingmenas for retainin it in operative position on the machine, sai latchingmeans being releasable by rotation of said sleeve, and a spring ringencircling said sleeve with one end projecting inwardly through anopening in said sleeve to engage an axial recess in said machine,thereby to permit instant application of said sleeve and releasably tolock said sleeve against accidental rotation.

6. The combination with the cylinder of a pneumatic hammer, saidcylinder having a groove providing a stop shoulder, of means fordetachably retaining a working tool in operative relation therewithcomprising a sleeve engaging the cylinder and having a latching memberadapted to seat in said groove and engage said step shoulder, saidmember being arranged to be 'forced out ,of said groove to release saidsleeve on rotation of the latter on'said cylinder, and locking means forpositively areventing such rotative movement of said s eeveautomatically operable on applying said sleeve to said cylinder.

7. The combination with the cylinder of a pneumatic hammer, saidcylinder having grooves providing stop shoulders, of means fordetachably retaining av working tool in operative relation therewithcomprising a sleeve engaging the cylinder and having latching membersadapted to seat in saidv grooves and engage said stop shoulders, saidmembers being arranged to be forced out of said grooves to release saidsleeve on retation of the latter on said cylinder, and a retractablelocking member on said sleeve automatically engaging a recess in saidcylinder on application of said sleeve thereto positively to preventrotative movement of said sleeve.

8. The combination with the cylinder of a pneumatic hammer, saidcylinder having grooves providing stop shoulders-, of means fordetachably retaining a working tool in operative relation therewithcomprising a sleeve engaging the cylinder and having spring pressedlatching members adapted to seat in said grooves and engage said stopshoulders, said members being forced out a pneumatic hammer, saidcylinder having grooves providing stop shoulders, of means fordetachably retaining a working tool in operative relation therewithcomprising a 'sleeve engaging the cylinder and having spring pressedlatching members adapted to seat in said grooves and engage said stopshoulders, said members being forced out of said grooves to release saidsleeve on rotation of the latter on said cylinder, and a locking memberextending through an opening in said sleeve and automatically engagingan axial recess in said cylinder on application of said sleeve theretofor preventing accidental rotation of said sleeve, and a spring ringencircling said sleeve for yield ingly holding said locking member inoperative position. 7

10. The combination with the cylinder of a pneumatic hammer, saidcylinder having transverse grooves providing stop shoulders and axialgrooves in a definite relation to said transverse grooves, of means fordetachably retaining a working tool in operative relation therewithcomprising a sleeve engaging the cylinder and having a circumferentialgroove, a spring seated in said groove, latching blocks carried by saidspring extending through openings in said sleeve to seat in saidtransverse cylinder grooves and engage said stop shoulders, said blocksbeing forced out of said grooves to release said sleeve on rotation ofthe latter on' said cylinder, a spring ring encircling said sleeve andcarrying a locking member which extends through an opening in saidsleeve automatically to engage one of said axial grooves of saidcylinder on application of said sleeve thereto thereby-to lock saidsleeve against accidental rotation movements, and

means adjacent said spring ring to permit the insertion of an instrumentfor lifting said locking member to unlock said sleeve.

11. A tool retaining. device for use with percussive machines comprisinga sleeve of a size to pass over the cylinder of the percussive machine,means on said sleeve for cooperation with grooves in said cylinder toprevent axial withdrawal of said sleeve, said means being arranged to bereleased on rotative movement of said sleeve, and means for cooperationwith a recess in said cylinder automatically and positively to lock saidsleeve against rotation.

12. A toolretaining device for use with percussive machines comprising asleeve of a size to pass over the cylinder of the percussive machine,means on said sleeve for cooperation with grooves said cylinder toprevent axial withdrawal of said sleeve,

said means being arranged to be released on rotative movement of saidsleeve, and a retractable member arranged automatically to engage arecess in said cylinder on application of the sleeve thereto positivelyto lock said sleeve against accidental rotative movement.

13. A tool retaining device for use with percussive machines comprisinga sleeve of 1 a size to pass over the cylinder of the percussivemachine, means on said sleeve for cooperation with grooves in saidcylinder to prevent axial withdrawal of said sleeve, said means beingarranged to be released on rotative movement of said sleeve, and aspring-pressed member arranged automatically to engage an axial groovein said cylinder positively to prevent accidental rotation of saidsleeve.

14. A tool retaining device for use with percussive machines comprisinga sleeve of a size to pass over the cylinder of the per= cussivemachine, a spring pressed latching block on said sleeve for cooperationwith a groove in said cylinder to prevent axial withdrawal of saidsleeve, said block being released on rotative movement of said sleeve onsaid cylinder, and a spring pressed lock-= ing member projecting throughan opening in said sleeve automatically toengage an axial recess in saidcylinder positlvely to prevent accidental rotative movement of saidsleeve.

' 15 A tool retaining device for use with percussive machines comprisinga sleeve of 0 size to pass over the cylinder of the per: cussivemachine, spring pressed latching blocks on said sleeve for cooperationwith shoulders on said cylinder to prevent axial withdrawal of saidsleeve in at least one position of the latter on' said cylinder, and a'spring ring encircling saidsleeve with one end projecting inwardlythrough an opening therein automatically to engage an axial reces's insaid cylinder on application of the sleeve thereto thereby to retainsaid sleeve in said position.

16. A tool retaining device for use with'lj. percussive machinescomprising a sleeve of a size to pass over the cylinder of thepercussive machine, spring pressed latching blocks on said sleeve forcooperation with shoulders on said cylinder to prevent axial withdrawalof said sleeve in at least one position of the letter on said cylinder,a spring ring encircling said sleeve with one end projecting inwardlythrough an opening t erein automatically to engage an axial recess insaid cylinder thereby to retainsaid sleeve in said position, and meansproviding for the liftin of said ring to prevent rota- 1 tion of said seeve and its release from said cylinder.

Signed by me at Detroit, Michigan this 5th day of December, 1924.

EDWARD W. STEVENS.

